到目前为止，我对所有给出的答案都不满意。他们还是太啰嗦了。在代码和消息输出中。

所有我想要的是stacktrace指向源异常，没有异常之间的东西，所以没有创建新的异常，只是重新提升原始与所有相关的堆栈帧状态在它，导致那里。

史蒂夫·霍华德给出了一个很好的答案，我想扩展一下，不，是简化一下……仅适用于python 3。

except Exception as e:
    e.args = ("Some failure state", *e.args)
    raise

唯一的新东西是参数展开/解包，这使得它对我来说足够小和容易使用。

试一试:

foo = None

try:
    try:
        state = "bar"
        foo.append(state)

    except Exception as e:
        e.args = ("Appending '"+state+"' failed", *e.args)
        raise

    print(foo[0]) # would raise too

except Exception as e:
    e.args = ("print(foo) failed: " + str(foo), *e.args)
    raise

这将给你:

Traceback (most recent call last):
  File "test.py", line 6, in <module>
    foo.append(state)
AttributeError: ('print(foo) failed: None', "Appending 'bar' failed", "'NoneType' object has no attribute 'append'")

简单的漂亮图案可以是这样的

print("\n".join( "-"*i+" "+j for i,j in enumerate(e.args)))

在PEP 678中，本机支持向异常添加注释:

try:
  raise TypeError('bad type')
except Exception as e:
  e.add_note('Add some information')
  raise

呈现为:

Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
TypeError: bad type
Add some information

我跳它可以取代史蒂夫霍华德的解决方案，不幸的是，它不给用户任何控制如何格式化最终的异常(例如，不能在异常之前添加一个注释，如:'错误在fn: {original_exc}')

如果想要对回溯进行更多控制，可以使用https://github.com/google/etils:

from etils import epy

with epy.maybe_reraise('Error in fn: '):
  fn()

Or:

try:
  fn()
except Exception as e:
  epy.reraise(e, suffix='. Did you mean y ?')

也许

except Exception as e:
    raise IOError(e.message + 'happens at %s'%arg1)

您可以定义从另一个异常继承的自己的异常，并创建它自己的构造函数来设置值。

例如:

class MyError(Exception):
   def __init__(self, value):
     self.value = value
     Exception.__init__(self)

   def __str__(self):
     return repr(self.value)

这是我的实现，使用它作为上下文管理器，并可选地添加额外的消息异常:

from typing import Optional, Type
from types import TracebackType

class _addInfoOnException():
    def __init__(self, info: str = ""):
        self.info = info

    def __enter__(self):
        return

    def __exit__(self,
                 exc_type: Optional[Type[BaseException]],
                 exc_val: BaseException,  # Optional, but not None if exc_type is not None
                 exc_tb: TracebackType):  # Optional, but not None if exc_type is not None
        if exc_type:
            if self.info:
                newMsg = f"{self.info}\n\tLow level error: "
                if len(exc_val.args) == 0:
                    exc_val.args = (self.info, )
                elif len(exc_val.args) == 1:
                    exc_val.args = (f"{newMsg}{exc_val.args[0]}", )
                elif len(exc_val.args) > 0:
                    exc_val.args = (f"{newMsg}{exc_val.args[0]}", exc_val.args[1:])
            raise

用法:

def main():
    try:
        raise Exception("Example exception msg")
    except Exception:
        traceback.print_exc()
        print("\n\n")

    try:
        with _addInfoOnException():
            raise Exception("Example exception msg, no extra info")
    except Exception:
        traceback.print_exc()
        print("\n\n")

    try:
        with _addInfoOnException("Some extra info!"):
            raise Exception("Example exception msg")
    except Exception:
        traceback.print_exc()
        print("\n\n")


if __name__ == "__main__":
    main()

这将在这样的跟踪中解决:

Traceback (most recent call last):
  File "<...>\VSCodeDevWorkspace\testis.py", line 40, in main
    raise Exception("Example exception msg")
Exception: Example exception msg



Traceback (most recent call last):
  File "<...>\VSCodeDevWorkspace\testis.py", line 47, in main
    raise Exception("Example exception msg, no extra info")
  File "<...>\VSCodeDevWorkspace\testis.py", line 47, in main
    raise Exception("Example exception msg, no extra info")
Exception: Example exception msg, no extra info



Traceback (most recent call last):
  File "<...>\VSCodeDevWorkspace\testis.py", line 54, in main
    raise Exception("Example exception msg")
  File "<...>\VSCodeDevWorkspace\testis.py", line 54, in main
    raise Exception("Example exception msg")
Exception: Some extra info!
        Low level error: Example exception msg

假设你不想或不能修改foo()，你可以这样做:

try:
    raise IOError('stuff')
except Exception as e:
    if len(e.args) >= 1:
        e.args = (e.args[0] + ' happens',) + e.args[1:]
    raise

这确实是在Python 3中解决问题的唯一解决方案，而不会出现丑陋而令人困惑的“在处理上述异常期间，发生了另一个异常”消息。

如果要将重新提升的行添加到堆栈跟踪中，则应该写入raise e而不是raise。